Effects of suspended sediment content on biodegradation of three common endocrine disruptors in river water

Abstract

Bisphenol A (BPA), 17β-oestradiol (E2) and 17α-ethynylestradiol (EE2) are common endocrine disruptors (EDs) in river water, and biodegradation is regarded as an important process for their removal from river water. The suspended sediment (SS) content is very high in some rivers, which may affect the biodegradation of these EDs. In this study, the degradation of BPA, E2 and EE2 in river water with different SS contents was investigated using batch experiments. The results show that the biodegradation rates of BPA, E2 and EE2 increase with the SS content in water samples. The half-lives of BPA, E2 and EE2 are 2.44–52.51 days, 0.40–6.38 days and 3.47–25.77 days, respectively, at SS contents ranging from 0 g L–1 to 15 g L–1. Micrographs demonstrate more bacteria in the SS than in the water phase. Higher SS concentrations provide greater surface areas for bacterial attachment and these bacteria apparently accelerate the biodegradation of common EDs.